Ran some quick tests, noticed that the velocity pass contains some higher values than I was expecting, and it makes using that pass tricky, at least in AE with ReelSmartMB.
Here’s the render, and the velocity pass - I’ve marked RGB values. Normal range is 0-1, extreme overbrights head up to 2, but you can see here that there’s values of +/- 30. Is this expected? Also I noticed the alpha was active in the velocity pass, which is an error I think?
This could easily be due to me doing something stupid, I’ve only had the plugin running for a couple of hours so I’m still getting my head around it. Using X-Particles by the way.
The Velocity Pass stores real-world units per second in camera space.
For example, if I create a classical Emitter with Speed 100cm, rotate to point it up and render that from a front facing camera, I get values of 100.0 along the Y and 0 along X and Z.
When using the data in Nuke, Fusion etc, you can rescale the values as you want them. If you need the Velocity to be Units Per Frame, multiply by 1.0/FrameRate (e.g. 1.0/24 = 0.0416666).
While we provide a normalized option in KMX, in KMY, KC4D and KSR in general we try to output real world data to OpenEXR so you can manipulate it according to scene scale and frame rate.
That being said, most of the passes output to EXR make very little sense in the world of volumetric rendering because they represent only the data of the closest particle to the camera, completely disregarding the hundreds or thousands of particles behind it. So in many cases the passes are there because people have asked for them, not because they are actually very useful The only pass that really makes sense is the Occluded Particles one. Here is the KMY documentation about it which applies to all Krakatoa versions: thinkboxsoftware.com/kmy-com … nd-mattes/
The only pass that really makes sense is the Occluded Particles one. Here is the KMY documentation about it which applies to all Krakatoa versions: